From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zach Brown Subject: tune back idle cwnd closing? Date: Fri, 21 Apr 2006 12:58:56 -0700 Message-ID: <44493980.1040708@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from tetsuo.zabbo.net ([207.173.201.20]:50074 "EHLO tetsuo.zabbo.net") by vger.kernel.org with ESMTP id S1751285AbWDUT7A (ORCPT ); Fri, 21 Apr 2006 15:59:00 -0400 Received: from [127.0.0.1] (unknown [207.173.201.20]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by tetsuo.zabbo.net (Postfix) with ESMTP id C4F1A2FD0430 for ; Fri, 21 Apr 2006 12:58:59 -0700 (PDT) To: netdev@vger.kernel.org Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org My apologies if this is a FAQ, I couldn't find it in the archives. We have some dudes who are syncing large amounts of data across a dedicated long fat pipe at somewhat irregular intervals that are, sadly, longer than the rto. They feel the pain of having to reopen the window between transmissions. Is there room for a compromise tunable that would be less aggressive about closing cwnd during idle periods but which wouldn't violate the spirit of 2861? No one wants broken TCP here. They mention that Solaris has the tcp_slow_start_after_idle tunable and that it helps their situation. I mention that only as a data point, I wouldn't be foolish enough to try and use the presence of something in Solaris as justification :) - z